The newest threat to the industry is a four-year-old condition called colony collapse disorder in which adult bees leave the hive and never return. More than a quarter of the honeybee population has disappeared each year since the problem started. This past winter, losses reached nearly 34 percent of the population, renewing concerns about the long-term viability of the industry.

Todd Youngblood, a Pearsall beekeeper who is president of the Texas Beekeepers Association, was not aware of the new study but said he hopes it starts to answer questions about the cause of the disorder.

“It’s a difficult problem,” he said.

Texas has about 500,000 bee colonies, part of a larger industry that provides pollination services to more than 90 commercial crops each year. The agriculture department estimates the industry adds $15 billion in value to those crops.